Vehicle energy recovery method, device and computer readable storage medium

Abstract

The application discloses a vehicle energy recovery method and device and a computer readable storage medium. The method relates to the field of intelligent automobiles, and comprises the following steps: in response to receiving a brake instruction, determining a driver demand torque based on the brake instruction; processing the driver demand torque by using a five-section slope filtering algorithm to obtain a target demand torque; obtaining the sum of a brake recovery demand torque sent by a vehicle body stability controller in the vehicle and the target demand torque to obtain a total demand torque; and controlling an electric machine in the vehicle based on the total demand torque. The application solves the technical problem that the driving comfort is poor due to the shaking of the vehicle when the driving and braking conditions of the vehicle are switched.

Description

Technical Field

[0001] The present invention relates to the field of smart cars, and in particular to a vehicle energy recovery method, device, and computer-readable storage medium. Background Art

[0002] Vehicle comfort is currently a key consideration for vehicle buyers. A vehicle that offers excellent driving comfort can reduce the risk of fatigue, discomfort, and even injury during extended driving, leading to more stable and reliable driving. Furthermore, an excellent driving experience is a major factor in selecting a particular vehicle or brand. However, traditional vehicles experience a certain degree of vibration when switching between driving and braking modes, resulting in poor driving comfort.

[0003] To address the above-mentioned problems, no effective solutions have been proposed so far. Summary of the Invention

[0004] Embodiments of the present invention provide a vehicle energy recovery method, device, and computer-readable storage medium to at least solve the technical problem of poor driving comfort caused by vehicle shaking when switching between driving and braking conditions.

[0005] According to one aspect of an embodiment of the present invention, a vehicle energy recovery method is provided, comprising: in response to receiving a braking command, determining a driver demand torque based on the braking command; processing the driver demand torque using a five-segment slope filtering algorithm to obtain a target demand torque; obtaining the sum of the braking recovery demand torque and the target demand torque sent by a body stability controller in the vehicle to obtain a total demand torque; and controlling a motor in the vehicle based on the total demand torque.

[0006] Optionally, the method also includes: acquiring motor data, allowable battery charging power and preset coasting recovery torque of the vehicle, wherein the motor data includes at least motor speed, motor external characteristics, and motor efficiency, and the preset coasting recovery torque is used to characterize the braking recovery torque during the vehicle coasting process; based on the acquired motor data, allowable battery charging power and preset coasting recovery torque, determining the braking recovery capability corresponding to the vehicle body stability controller; sending the braking recovery capability to the vehicle body stability controller, wherein the braking recovery capability is used to control the vehicle body stability controller to send the braking recovery requirement torque, and the braking recovery requirement torque is less than or equal to the braking recovery capability.

[0007] Optionally, the determining the brake recovery capability corresponding to the vehicle body stability controller based on the motor data, the battery allowable charging power and the preset coasting recovery torque comprises: determining a first demand torque based on the motor data and the battery allowable charging power; determining a second demand torque by taking the minimum value between the first demand torque and the preset coasting recovery torque; and obtaining the brake recovery capability by taking the difference between the first demand torque and the second demand torque.

[0008] Optionally, the sending the brake recovery capability to the vehicle body stability controller comprises: in response to the total demand torque being less than a preset threshold and waiting for a preset time, sending the brake recovery capability to the vehicle body stability controller.

[0009] Optionally, after controlling the motor in the vehicle based on the total demand torque, the method further comprises at least one of the following: in response to the accelerator pedal of the vehicle being in a priority working condition, clearing the brake recovery capability; in response to a first vehicle speed of the vehicle being less than a first preset vehicle speed and the first vehicle speed being greater than a second preset vehicle speed, starting to clear the brake recovery capability, and in response to a second vehicle speed of the vehicle being less than or equal to the second preset vehicle speed, ending the clearing of the brake recovery capability.

[0010] Optionally, the clearing the brake recovery capability in response to the accelerator pedal of the vehicle being in a priority working condition comprises: obtaining a current brake recovery torque request value of the vehicle body stability controller, wherein the current brake recovery torque request value is used to represent the current required brake recovery torque of the vehicle body stability controller; determining a change slope of the brake recovery capability based on the current brake recovery torque request value, wherein the change slope at least comprises a first slope and a second slope; and clearing the brake recovery capability according to the change slope of the brake recovery capability.

[0011] Optionally, the determining the current change slope of the brake recovery capability comprises: in response to the brake recovery capability being greater than the current brake recovery torque request value, determining the change slope as the first slope; and in response to the brake recovery capability being less than or equal to the current brake recovery torque request value, determining the change slope as the second slope.

[0012] Optionally, the starting to clear the brake recovery capability in response to the first vehicle speed of the vehicle being less than the first preset vehicle speed and the first vehicle speed being greater than the second preset vehicle speed comprises: clearing the brake recovery torque; and in response to the clearing of the brake recovery torque, clearing the second demand torque.

[0013] According to another aspect of an embodiment of the present invention, a vehicle energy recovery device is also provided, including: a determination module for determining the driver's required torque based on the braking command in response to receiving the braking command; a processing module for processing the driver's required torque using a five-segment slope filtering algorithm to obtain a target required torque; an acquisition module for obtaining the sum of the braking recovery required torque and the target required torque sent by the body stability controller in the vehicle to obtain a total required torque; and a control module for controlling the motor in the vehicle based on the total required torque.

[0014] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is further provided. The computer-readable storage medium includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute the vehicle energy recovery method of the above embodiment.

[0015] According to another aspect of an embodiment of the present invention, a vehicle is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute the vehicle energy recovery method of the above embodiment.

[0016] In an embodiment of the present invention, in response to receiving a braking command, a driver demand torque is determined based on the braking command; the driver demand torque is processed using a five-stage slope filtering algorithm to obtain a target demand torque; the sum of the braking regeneration demand torque sent by a vehicle stability controller and the target demand torque is obtained to obtain a total demand torque; and a motor in the vehicle is controlled based on the total demand torque. It should be noted that using the five-stage slope filtering algorithm to process the driver demand torque can make the target demand torque smoother, and then add the braking regeneration demand torque to obtain the total demand torque, and control the motor based on the total demand torque, effectively avoiding knocking vibration caused by rapid engagement of transmission gears, thereby ensuring smooth driving when switching between driving and braking conditions, achieving the purpose of improving the driver's driving experience, and achieving the technical effect of avoiding knocking vibration caused by rapid torque changes during the vehicle switching between driving and braking conditions, thereby solving the technical problem of vehicle jitter and poor driving comfort when switching between driving and braking conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 is a flow chart of a vehicle energy recovery method according to an embodiment of the present invention;

[0019] Figure 2is a schematic diagram of an optional five-segment slope according to an embodiment of the present invention;

[0020] Figure 3 is a schematic diagram of an optional braking regenerative torque software architecture according to an embodiment of the present invention;

[0021] Figure 4 is a schematic diagram of an optional process of starting superimposed braking regenerative torque according to an embodiment of the present invention;

[0022] Figure 5 is a schematic diagram of an optional process of ending superimposed braking regenerative torque according to an embodiment of the present invention;

[0023] Figure 6 is a flow chart of an optional vehicle energy recovery method according to an embodiment of the present invention;

[0024] Figure 7 is a schematic diagram of a vehicle energy recovery device according to an embodiment of the present invention; DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] Example 1

[0028] According to an embodiment of the present invention, an embodiment of a vehicle energy recovery method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0029] Figure 1 A vehicle energy recovery method according to an embodiment of the present invention is as follows. Figure 1 As shown, the method includes the following steps:

[0030] In step S102 , in response to receiving a braking command, determining a driver demand torque based on the braking command.

[0031] The above-mentioned braking command can be a stop or deceleration command issued by the driver to the vehicle by stepping on the brakes while the vehicle is running, etc., which is used to control the vehicle's speed and ensure safe driving.

[0032] The driver demand torque mentioned above may be the braking torque required by the driver to decelerate the vehicle to a demand speed or stop the vehicle during driving.

[0033] In an optional embodiment, upon detecting the driver's application of the brake pedal, a corresponding brake signal is generated and sent to the vehicle controller. The vehicle controller then obtains the brake pedal angle and the rate of change of the brake pedal angle within a certain period of time based on the brake signal. Based on the brake pedal angle at the time the driver applied the brake and the rate of change of the brake pedal angle within a certain period of time, the vehicle controller determines a corresponding braking command, which is then sent to the vehicle controller. The vehicle controller then calculates the driver's required torque. The brake pedal can be detected by a sensor and the corresponding brake signal generated.

[0034] In another optional embodiment, the driver inputs braking voice, including but not limited to: decelerating from the current speed to a certain speed. The voice system analyzes the driver's braking voice, obtains the corresponding braking command and sends it to the vehicle control system. After the vehicle control system receives the braking command sent by the driver, it obtains the driver's required torque according to the braking command.

[0035] Step S104 : Processing the driver's required torque using a five-segment slope filtering algorithm to obtain a target required torque.

[0036] The above-mentioned five-segment slope filtering algorithm can be a filtering algorithm that removes the portion of the driver's demand torque that does not meet the five-segment slope, or it can be an algorithm that uses the five-segment slope to limit the rising / falling slope of the driver's demand torque, so that the driver's demand torque meets the drivability requirements. Among them, the five-segment slope can be the slope of the demand torque generated by the driver when driving the vehicle, divided into five sections, including but not limited to: positive torque zero-crossing slope section, negative torque zero-crossing slope section, normal climbing slope section, normal falling slope section, and approaching target torque slope section. Among them, Figure 2 is a schematic diagram of an optional five-segment slope according to an embodiment of the present invention, such as Figure 2 As shown, the horizontal axis is time, and the vertical axis is vehicle torque demand. The dashed line represents the driver demand torque without the five-stage slope filtering algorithm, and the solid line represents the driver demand torque after the five-stage slope filtering algorithm is used. a1 represents the positive approach-to-target torque slope, a2 represents the negative approach-to-target torque slope, b1 represents the normal ramp-up slope, b2 represents the normal ramp-down slope, and c represents the positive and negative torque zero-crossing slopes. The positive torque zero-crossing slope section is where the torque is positive and close to zero; the negative torque zero-crossing slope section is where the torque is negative and close to zero; the normal ramp-up slope section is where the torque is positive and the torque demand falls between the approach-to-target torque slope section and the positive torque zero-crossing slope section; and the normal ramp-down slope section is where the torque is negative and the torque demand falls between the approach-to-target torque slope section and the negative torque zero-crossing slope section. The approach-to-target torque slope section represents the torque slope required for the vehicle's current driving situation. The positive and negative torque zero-crossing ramps are designed to prevent rattling vibration caused by rapid gear engagement in the transmission. The normal climbing and descending ramps are designed to accommodate driving styles with varying throttles, vehicle speeds, and driving modes. The target torque ramp requires a smooth transition as the torque approaches the target torque to prevent a sudden decrease in the torque ramp, which could cause the transmission to vibrate similarly to a step excitation.

[0037] The target required torque may be a braking torque required for decelerating or stopping the vehicle.

[0038] It should be noted that there is a gap in the transmission system where the motor is located. When the motor torque crosses zero, that is, when the positive torque zero-crossing slope segment in the driver's demand torque transitions to the negative torque zero-crossing slope segment, the transmission system gears will fit from one side to the other. If the driver's demand torque changes too quickly, that is, the slope is too large, it will cause the transmission system gears to fit quickly, resulting in knocking vibration, causing the vehicle to shake violently, resulting in a poor driving experience for the driver. In an optional embodiment, after obtaining the driver's demand torque, the driver's demand torque is analyzed to obtain the slope of the driver's demand torque. The slope is calibrated based on the driver's demand torque without considering the maximum rate allowed by the vehicle stability controller (ESC) hydraulic braking and electric braking switching. A five-segment slope filtering algorithm is used to limit the driver's demand torque to within the five-segment slope, so that the driver's demand torque meets the five-segment slope requirements, thereby obtaining the target demand torque. Using a five-stage slope filtering algorithm to process the driver's demanded torque can effectively avoid knocking vibrations caused by the rapid engagement of the transmission gears in the motor, and prevent the transmission zero-crossing jitter shock caused by the superimposed braking recovery torque when the driver switches between driving and braking conditions, causing the vehicle to experience severe jitter, thereby improving the driver's driving experience.

[0039] Step S106 , obtaining the sum of the braking recovery required torque and the target required torque sent by the vehicle body stability controller in the vehicle to obtain the total required torque.

[0040] The above-mentioned vehicle may be a vehicle capable of achieving braking recovery, including but not limited to: a pure electric vehicle.

[0041] The vehicle stability controller (VSC) is an electronic control system that monitors the vehicle's dynamic conditions and adjusts parameters such as the suspension, brakes, and engine output to ensure more stable driving during cornering or sudden changes of direction. Sensors can detect information such as the vehicle's roll, slip, and rotation angle, and based on this information, the optimal control strategy is calculated in real time to prevent accidents such as rollover and loss of control.

[0042] The regenerative braking demand torque is the torque required for braking. It depends on factors such as vehicle speed, mass, friction between the tires and the road, and the braking system. The vehicle stability controller will respond to its own conditions and will not exceed the regenerative braking capacity specified by the vehicle controller.

[0043] The total required torque may be the required torque received by the motor controller (MCU) to control the operation of the motor, or may be the required torque obtained by adding the target required torque to the braking recovery required torque.

[0044] In an optional embodiment, after receiving the brake recovery demand torque sent by the body stability controller, the vehicle controller superimposes the brake recovery demand torque to the target demand torque to obtain a total demand torque, and sends the total demand torque to the motor controller.

[0045] In step S108, the motor in the vehicle is controlled based on the total demand torque.

[0046] The motor described above can be a device that converts electrical energy into mechanical energy, which produces force and motion by acting on a conductor through a magnetic field. It includes but is not limited to: DC motor, AC asynchronous motor, AC synchronous motor.

[0047] In an optional embodiment, after the motor controller obtains the total demand torque, the motor in the vehicle is controlled according to the total demand torque. During the driving process of the vehicle, sudden events may occur, and the total demand torque may change due to changes in the target demand torque and / or the brake recovery demand torque. Therefore, the motor controller controls the motor according to the latest total demand torque updated in real time.

[0048] Through the above steps, the following technical effects can be achieved: in response to receiving a brake instruction, determining a driver demand torque based on the brake instruction; using a five-segment slope filtering algorithm to process the driver demand torque to obtain a target demand torque; obtaining the sum of the brake recovery demand torque sent by the body stability controller in the vehicle and the target demand torque to obtain a total demand torque; and controlling the motor in the vehicle based on the total demand torque. It should be noted that using a five-segment slope filtering algorithm to process the driver demand torque can make the target demand torque more gentle, and then superimpose the brake recovery demand torque to obtain the total demand torque, and control the motor according to the total demand torque, effectively avoiding the rapid fitting of the transmission system gear to cause knocking vibration, so that the vehicle runs smoothly when the driving and braking conditions are switched, and the purpose of improving the driving experience of the driver is achieved. The technical effect of avoiding the rapid fitting of the transmission system gear to cause knocking vibration caused by the rapid change of the torque when the driving and braking conditions of the vehicle are switched is achieved, and the technical problem of poor driving comfort caused by the shaking of the vehicle when the driving and braking conditions of the vehicle are switched is solved.

[0049] It should be noted that, Figure 3 is a schematic diagram of an optional brake recovery torque software architecture according to an embodiment of the present application, as Figure 3As shown, the vehicle controller calculates the driver's requested torque and uses a five-stage slope filter algorithm to limit the driver's requested torque to obtain the target requested torque. The vehicle controller then sends the regenerative braking capability and regenerative braking torque request value to the body stability controller to determine the regenerative braking torque request. The target requested torque and the regenerative braking torque request are then added together to obtain the total requested torque. This total requested torque is then sent to the motor for execution. This effectively avoids the powertrain's zero-crossing jitter caused by the added regenerative braking torque when switching between driving and braking modes.

[0050] Optionally, the method also includes: acquiring motor data, allowable battery charging power and preset coasting recovery torque of the vehicle, wherein the motor data includes at least motor speed, motor external characteristics, and motor efficiency, and the preset coasting recovery torque is used to characterize the braking recovery torque during the vehicle coasting process; based on the acquired motor data, allowable battery charging power and preset coasting recovery torque, determining the braking recovery capability corresponding to the vehicle body stability controller; sending the braking recovery capability to the vehicle body stability controller, wherein the braking recovery capability is used to control the vehicle body stability controller to send the braking recovery requirement torque, and the braking recovery requirement torque is less than or equal to the braking recovery capability.

[0051] The above-mentioned motor data can be the performance index and operation data of the motor, including but not limited to: motor speed, motor external characteristics, and motor efficiency. Among them, the motor speed can be the calibration of the speed when the motor is running. Different types of motors have different rated speed ranges. During operation, it is necessary to pay attention to its maximum allowable speed and load capacity measured in revolutions per minute. The motor external characteristics can be the basic parameters of the motor. The motor efficiency can be the efficiency of the motor when it is running. Under certain load conditions, the motor output power, efficiency, speed and other parameters change with the input voltage, frequency or DC bias current. By measuring and analyzing these characteristic curves, the appropriate working range of the motor can be determined and the appropriate control method and driver can be selected.

[0052] The preset coasting recovery torque can be a coasting recovery torque set in advance according to specific circumstances, and can be the required torque when the driver releases the accelerator and does not step on the brake. 滑行回收扭矩需求Raw express.

[0053] The battery's allowable charging power, as described above, refers to the maximum charging power a battery can safely accept within a specified timeframe. This value is typically specified by the manufacturer and varies depending on the battery model and size. Fast charging exceeding this allowable charging power may cause battery overheating, capacity loss, or even explosion. Therefore, it's important to adhere to the manufacturer's recommended charging method and time.

[0054] The aforementioned braking recovery capability may be the capability corresponding to the braking recovery demand torque sent by the vehicle controller to control the vehicle body stability controller.

[0055] In an optional embodiment, the motor's external characteristics are directly acquired from the motor assembly, and vehicle driving data recorded on the Controller Area Network (CAN) bus is used to determine the motor speed, motor efficiency, battery charging power allowable, and preset coasting regenerative torque. The motor data, required battery charging power, and preset coasting regenerative torque are then used to calculate the corresponding regenerative braking capability of the vehicle stability controller. This regenerative braking capability is then transmitted to the vehicle stability controller, which then transmits the required regenerative braking torque within its regenerative braking capability according to its own conditions.

[0056] Optionally, based on the motor data, the battery's allowable charging power and the preset coasting recovery torque, the braking recovery capability corresponding to the vehicle stability controller is determined, including: determining a first required torque based on the motor data and the battery's allowable charging power; determining a second required torque by obtaining the minimum value between the first required torque and the preset coasting recovery torque; and obtaining the difference between the first required torque and the second required torque to obtain the braking recovery capability.

[0057] The first required torque can be the vehicle's braking recovery torque. The second required torque can be the vehicle's coasting recovery torque, which can be expressed as T 滑行回收扭矩需求 express.

[0058] By controlling the sequence of clearing the first required torque and the second required torque, it is possible to avoid the torque passing through zero too quickly, which would cause the transmission gears to quickly engage and cause knocking vibration, resulting in severe shaking of the vehicle and a poor driving experience for the driver.

[0059] In an optional embodiment, after obtaining the motor data, the battery allowable charging power, and the preset coasting recovery torque, the motor data and the battery allowable charging power are substituted into a formula to determine the first required torque. The specific formula is:

[0060] MIN[(p 电池许用充电功率 *9550 / n 电机转速 ) / μ 效率 , T 电机外特性 ]

[0061] The minimum value between the first required torque and the preset coasting recovery torque is obtained to obtain the second required torque T 滑行回收扭矩需求 , the specific formula is:

[0062] T 滑行回收扭矩需求

[0063] =MIN(T 滑行回收扭矩需求RawMIN[(p 电池许用充电功率 9550 / n 电机转速 ) / μ 效率 , T 电机外特性 ]

[0064] Further, according to the formula:

[0065] T 制动回收能力 = MIN[(p 电池许用充电功率 9550 / n 电机转速 ) / μ 效率 , T 电机外特性 ]-T 滑行回收扭矩需求

[0066] The brake recovery capability is calculated.

[0067] Optionally, the brake recovery capability is sent to the vehicle body stability controller, comprising: in response to the total demand torque being less than a preset threshold and waiting for a preset time, the brake recovery capability is sent to the vehicle body stability controller.

[0068] The above-mentioned preset threshold can be a threshold set in advance according to specific circumstances, used to determine the time when the vehicle controller sends the brake recovery capability to the vehicle body stability controller. The preset threshold needs to be greater than the minimum torque at which the transmission gear can be attached to the other side, and can be but is not limited to: a value less than 0, such as -2 Nm, which can be represented by T 过零阈值 .

[0069] The above-mentioned waiting preset time can be the time set in advance by the vehicle controller to send the target demand torque, to ensure the timeliness of the target demand torque. The waiting preset time needs to be greater than the minimum time at which the transmission gear can be attached to the other side, and can be but is not limited to: 0.1 s.

[0070] In an optional embodiment, in order to ensure that the superimposed brake recovery torque does not impact after zero crossing, when the total demand torque sent by the vehicle controller to the motor controller is less than the preset threshold, and the time when the total demand torque sent by the vehicle controller to the motor controller is the waiting preset time, the vehicle controller sends the brake recovery capability to the vehicle body stability controller.

[0071] It's important to note that the vehicle controller's transmission of regenerative braking capability to the body controller cannot be determined based on the motor controller's actual torque being less than a threshold. This is because when motor anti-shake is engaged, the motor's actual torque will fluctuate, causing fluctuations in the regenerative braking capability sent by the vehicle controller to the body stability controller, exacerbating severe vibration in the motor drivetrain. Therefore, determining whether to send regenerative braking capability is based on whether the total demanded torque and the total demanded torque sent from the vehicle controller to the motor controller are less than a preset threshold, and whether the total demanded torque sent from the vehicle controller to the motor controller has waited for a preset time. This can effectively prevent fluctuations in regenerative braking capability that could cause vibration in the motor drivetrain.

[0072] Optionally, after controlling the motor in the vehicle based on the total required torque, the method also includes at least one of the following: clearing the braking recovery capability in response to the vehicle's accelerator pedal being in a priority operating condition; starting to clear the braking recovery capability in response to the vehicle's first speed being less than a first preset speed and the first speed being greater than a second preset speed, and ending to clear the braking recovery capability in response to the vehicle's second speed being less than or equal to the second preset speed.

[0073] The accelerator pedal mentioned above may be a pedal on a vehicle used by a driver to control vehicle acceleration.

[0074] The first vehicle speed may be the current speed of the vehicle or the speed of the vehicle after the brake pedal is depressed.

[0075] The above-mentioned first preset vehicle speed can be a vehicle speed set in advance according to specific circumstances, which is greater than the minimum vehicle speed (rotational speed) allowed for switching between ESC hydraulic braking and electric braking and greater than the vehicle speed threshold at which the coasting recovery demand torque begins to exit, and is used to determine whether to start clearing the braking recovery capability, which can be but is not limited to: 12km / h.

[0076] The above-mentioned second preset vehicle speed can be a vehicle speed set in advance according to specific circumstances, or it can be a vehicle speed threshold at which the coasting torque is exited at low speed, which is used to determine whether the braking recovery capability has been exited. It can be but is not limited to: 8km / h.

[0077] The second vehicle speed mentioned above may be the current speed of the vehicle, or the vehicle speed after the braking recovery capability starts to be cleared.

[0078] In an optional embodiment, when the vehicle identifies that the current accelerator pedal is in a priority working condition, the braking recovery capability needs to be cleared. The purpose is to prevent the superimposed braking recovery torque from destroying the torque zero point when the brake is switched to drive, resulting in a zero-crossing impact and causing the motor to vibrate. When the first speed of the vehicle is less than the preset speed and greater than the second preset speed, the vehicle controller starts to clear the braking recovery capability. When the vehicle starts to clear the braking recovery capability, the second speed of the vehicle is obtained. When the second speed is less than or equal to the second preset speed, the braking recovery capability is cleared. For example, when the current speed of the vehicle is less than 12km / h and greater than 8km / h, the vehicle controller starts to clear the braking recovery capability; when the vehicle speed is less than or equal to 8km / h, the vehicle controller ends clearing the braking recovery capability.

[0079] It should be noted that there are two throttle priority conditions: one is that the driver steps on the brake pedal first and then the accelerator; the other is that the vehicle turns on the automatic overtaking mode (Acc Ped Override) when the adaptive cruise control system (ACC) intervenes.

[0080] Optionally, in response to the vehicle's accelerator pedal being in a priority operating condition, the braking recovery capability is cleared, including: obtaining a current braking recovery torque request value of the vehicle stability controller, wherein the current braking recovery torque request value is used to characterize the braking recovery torque currently required by the vehicle stability controller; based on the current braking recovery torque request value, determining a change slope of the braking recovery capability, wherein the change slope includes at least: a first slope and a second slope; and clearing the braking recovery capability according to the change slope of the braking recovery capability.

[0081] The current braking regeneration torque request value mentioned above may be the braking regeneration torque currently required by the vehicle stability controller to control the vehicle, and is not limited by the braking regeneration capability.

[0082] The aforementioned slope of change may be the slope of change of the vehicle's regenerative braking torque, including but not limited to a first slope and a second slope. The first slope may be the larger of the regenerative braking capacity slopes, and may be, but not limited to, -20,000 Nm / s. The second slope may be the smaller of the regenerative braking capacity slopes, and may be, but not limited to, -2000 Nm / s. The second slope is determined so as not to exceed the maximum rate allowed by the ESC hydraulic braking and electric braking switching.

[0083] In an optional embodiment, when the accelerator pedal of the vehicle is in a priority working state, that is, when the driver steps on the brake pedal and then steps on the accelerator pedal again, it is necessary to respond to the driver's driving torque (positive) again. At this time, the braking recovery torque needs to be cleared. In order to prevent the driving torque from increasing, the total torque superposition positive and negative changes quickly when the braking torque decreases, and the braking recovery capacity needs to be cleared according to the change slope of the braking recovery capacity. First, the current braking recovery torque request value of the vehicle body stability controller is obtained, and the braking recovery capacity sent by the vehicle controller to the vehicle body stability controller is compared with the current braking recovery torque request value to determine the change slope of the braking recovery capacity. If the current braking recovery torque request value is less than the first slope and greater than the second slope, the vehicle controller clears the braking recovery capacity.

[0084] It should be noted that if the current regenerative braking torque request is greater than the first slope, the vehicle controller will reset the regenerative braking capacity, resulting in a slower reset. This can cause the regenerative braking torque to not be fully reset by the time the driver steps on the accelerator pedal again, causing the total torque to quickly cross zero, resulting in a certain impact. If the current regenerative braking torque request is less than the second slope, the vehicle controller will reset the regenerative braking capacity too quickly, resulting in the regenerative braking torque being cleared too quickly. The vehicle stability controller will not be able to compensate for the regenerative braking torque with wheel cylinder hydraulic pressure in time, resulting in a further impact.

[0085] Optionally, determining the current change slope of the braking recovery capability includes: in response to the braking recovery capability being greater than the current braking recovery torque request value, determining the change slope to be a first slope; in response to the braking recovery capability being less than or equal to the current braking recovery torque request value, determining the change slope to be a second slope.

[0086] In an optional embodiment, if the braking recovery capability sent by the vehicle controller to the body stability controller is greater than the current braking recovery torque request value, the current slope of the braking recovery capability is determined to be the first slope; if the braking recovery capability sent by the vehicle controller to the body stability controller is less than or equal to the current braking recovery torque request value, the current slope of the braking recovery capability is determined to be the second slope.

[0087] It should be noted that when the regenerative braking capability sent by the vehicle controller is greater than the current regenerative braking torque request, the slope of the current regenerative braking torque request must have both a zero-crossing slope segment and a slope segment close to the target value. This prevents driveline jerk caused by the vehicle stability controller's regenerative braking request when the vehicle controller sends the regenerative braking capability normally. The zero-crossing slope segment requires a smooth transition to zero when the ESC regenerative braking torque request is released, and the slope segment close to the target value requires a smooth transition to the target value when the ESC regenerative braking torque request reaches its target value.

[0088] Figure 4 FIG. 1 is a schematic diagram of an optional superimposed braking recovery torque starting process according to an embodiment of the present invention, as shown in FIG. Figure 4 In the figure, a represents the brake pedal state, b represents the driver's requested torque, c represents the wheel cylinder pressure, d represents the regenerative braking demand, e represents the motor's requested torque, and f represents the change in regenerative braking capacity. When the driver depresses the brake pedal, vehicle speed begins to decrease, and the driver's requested torque also decreases. In response to the regenerative braking torque starting to clear, the vehicle stability controller compensates for the regenerative braking torque with wheel cylinder hydraulic pressure. As the wheel cylinder pressure begins to decrease, the regenerative braking capacity, the regenerative braking demand, and the motor's requested torque all decrease.

[0089] Figure 5 FIG. 1 is a schematic diagram of an optional process of ending superimposed braking recovery torque according to an embodiment of the present invention. Figure 5 As shown, the solid line g is the vehicle speed. After the braking regeneration torque is cleared, the wheel cylinder pressure will recover and will no longer compensate for the braking regeneration torque. The braking regeneration capacity, braking regeneration demand, and motor demand will also gradually recover.

[0090] Optionally, in response to the vehicle's first speed being less than a first preset speed and the first speed being greater than a second preset speed, the braking recovery capability is cleared, including: clearing the braking recovery torque; and in response to the braking recovery torque being cleared, clearing the second required torque.

[0091] In an optional embodiment, in response to the vehicle's first speed being less than a first preset speed and the first speed being greater than a second preset speed, the braking recovery capability begins to be cleared, and the braking recovery torque needs to be cleared first. After the braking recovery torque is cleared, the second torque is cleared. This can avoid excessive coupling and clearing of the braking recovery torque demand and the coasting torque demand, resulting in destruction of the torque zero point and zero crossing impact, thereby ensuring smooth braking transition during low-speed parking.

[0092] In another optional embodiment, when the first vehicle speed is less than a first preset speed and greater than a third preset speed, the regenerative braking torque is reset. When the third vehicle speed is less than the third preset speed and greater than the second preset speed, the regenerative braking torque is reset. The third vehicle speed may be the vehicle speed after the regenerative braking torque is reset. The third preset speed may be a vehicle speed pre-set according to specific circumstances and used to determine whether the vehicle begins to reset the second required torque. When the second vehicle speed is less than or equal to the second preset speed and greater than a fourth preset speed, the regenerative braking torque is reset. The fourth preset speed may be a vehicle speed pre-set according to specific circumstances and used to determine whether to terminate the regenerative braking torque. When the fourth vehicle speed is less than or equal to the fourth preset speed, the regenerative braking torque is reset. The fourth speed may be the vehicle speed after the regenerative braking torque is reset. It should be noted that the first preset speed is greater than the third preset speed, and the second preset speed is greater than the fourth preset speed.

[0093] For example, when the vehicle speed is lower than 12km / h and greater than 10km / h, the vehicle controller starts to clear the braking recovery torque. When the vehicle speed is lower than 10km / h and greater than 8km / h, it starts to clear the second required torque. When the vehicle speed is lower than or equal to 8km / h and greater than 5km / h, the braking recovery torque clearing is terminated. When the vehicle speed V4 is lower than or equal to 5kmph, the second required torque clearing is terminated.

[0094] Figure 6 is a flow chart of an optional vehicle energy recovery method according to an embodiment of the present invention, such as Figure 6 As shown, the steps of this method are as follows:

[0095] Step S601: Detecting that the driver has stepped on the brake pedal.

[0096] Step S602: Obtain vehicle speed and total required torque.

[0097] In step S603 , the motor operates according to the total required torque, and the braking recovery torque is cleared based on the vehicle speed.

[0098] Step S604: clearing the second required torque based on the vehicle.

[0099] Example 2

[0100] According to another aspect of an embodiment of the present invention, a vehicle energy recovery device is also provided. The device can execute the vehicle energy recovery device in the above embodiment. The specific implementation method and preferred application scenario are the same as those in the above embodiment and will not be repeated here.

[0101] Figure 7is a schematic diagram of a vehicle energy recovery device according to an embodiment of the present invention, such as Figure 7 As shown, the device includes the following parts: a first determination module 70 , a processing module 72 , a first acquisition module 74 and a control module 76 .

[0102] The first determining module 70 is configured to determine the driver's required torque based on the braking command in response to receiving the braking command;

[0103] A processing module 72 is configured to process the driver's required torque using a five-segment slope filtering algorithm to obtain a target required torque;

[0104] A first acquisition module 74 is configured to acquire the sum of the braking recovery required torque and the target required torque sent by the vehicle body stability controller to obtain a total required torque;

[0105] The control module 76 is configured to control electric machines in the vehicle based on the total torque demand.

[0106] Optionally, the device also includes: a second acquisition module, used to acquire motor data, the battery's allowable charging power and the vehicle's preset coasting recovery torque, wherein the motor data includes at least motor speed, motor external characteristics, and motor efficiency, and the preset coasting recovery torque is used to characterize the braking recovery torque during the vehicle's coasting process; a second determination module, used to determine the braking recovery capability corresponding to the vehicle body stability controller based on the acquired motor data, the battery's allowable charging power and the preset coasting recovery torque; a starting module, used to send the braking recovery capability to the vehicle body stability controller, wherein the braking recovery capability is used to control the vehicle body stability controller to send the braking recovery requirement torque, and the braking recovery requirement torque is less than or equal to the braking recovery capability.

[0107] Optionally, the second determination module includes: a first determination unit, used to determine the first required torque based on motor data and the allowable charging power of the battery; a second determination unit, used to obtain the minimum value of the first required torque and the preset coasting recovery torque to determine the second required torque; and a first acquisition unit, used to obtain the difference between the first required torque and the second required torque to obtain the braking recovery capacity.

[0108] Optionally, the sending module includes: a sending unit, configured to send the braking recovery capability to the vehicle body stability controller in response to the total required torque being less than a preset threshold and waiting for a preset time.

[0109] Optionally, after the motor in the vehicle is controlled based on the total demand torque, the device further comprises at least one of the following: a clearing module configured to clear the brake recovery capability in response to the accelerator pedal of the vehicle being in a priority working condition; and an ending module configured to start clearing the brake recovery capability in response to a first vehicle speed of the vehicle being less than a first preset vehicle speed and the first vehicle speed being greater than a second preset vehicle speed, and end the clearing of the brake recovery capability in response to a second vehicle speed of the vehicle being less than or equal to the second preset vehicle speed.

[0110] Optionally, the clearing module comprises: a second obtaining unit configured to obtain a current brake recovery torque request value of a vehicle body stability controller, wherein the current brake recovery torque request value is used to represent a current required brake recovery torque of the vehicle body stability controller; a third determining unit configured to determine a change slope of the brake recovery capability based on the current brake recovery torque request value, wherein the change slope comprises at least a first slope and a second slope; and a first clearing unit configured to clear the brake recovery capability according to the change slope of the brake recovery capability.

[0111] Optionally, the third determining unit comprises: a first determining sub-unit configured to determine the change slope as the first slope in response to the brake recovery capability being greater than the current brake recovery torque request value, and determine the change slope as the second slope in response to the brake recovery capability being less than or equal to the current brake recovery torque request value.

[0112] Optionally, the ending module comprises: a second clearing unit configured to clear the brake recovery torque; and a third clearing unit configured to clear the second demand torque in response to the brake recovery torque being cleared.

[0113] Embodiment 3

[0114] According to another aspect of the embodiments of the present application, a computer readable storage medium is also provided, which comprises a stored program, wherein the program, when executed, controls the device where the computer readable storage medium is located to perform the vehicle energy recovery method of the above-mentioned embodiments.

[0115] Embodiment 4

[0116] According to another aspect of the embodiments of the present application, a vehicle is also provided, which comprises a memory and a processor, the memory stores a computer program, and the processor is configured to execute the computer program to perform the vehicle energy recovery method of the above-mentioned embodiments.

[0117] The above-mentioned serial numbers of the embodiments of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0118] In the above-mentioned embodiments of the present application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0119] In several embodiments provided in the present application, it should be understood that the disclosed technology can be implemented in other manners. For example, the described unit embodiments are merely schematic, and the division of units can be different from the above. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, and electrical or other forms.

[0120] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on multiple units. Some or all of the units can be selected according to actual needs to achieve the purposes of the embodiments.

[0121] In addition, each functional unit in the various embodiments of the present application can be integrated in a processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0122] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application, essentially or the part that contributes to the prior art, or all or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes several instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0123] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, several improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. A vehicle energy recovery method, characterized in that: include: In response to receiving a braking command, determining a driver demand torque based on the braking command; Processing the driver's required torque using a five-segment slope filtering algorithm to obtain a target required torque; Obtaining a sum of a braking recovery demand torque sent by a vehicle body stability controller in the vehicle and the target demand torque to obtain a total demand torque; controlling a motor in the vehicle based on the total required torque; After controlling the motor in the vehicle based on the total required torque, the method further includes at least one of the following: In response to the accelerator pedal of the vehicle being in a priority operating state, obtaining a current braking regenerative torque request value of the vehicle stability controller, wherein the current braking regenerative torque request value is used to represent the braking regenerative torque currently required by the vehicle stability controller; determining a change slope of a braking regenerative capability based on the current braking regenerative torque request value, wherein the change slope includes at least: a first slope and a second slope; and clearing the braking regenerative capability according to the change slope of the braking regenerative capability; In response to a first vehicle speed of the vehicle being less than a first preset vehicle speed and the first vehicle speed being greater than a second preset vehicle speed, starting to clear the braking recovery capability, and in response to a second vehicle speed of the vehicle being less than or equal to the second preset vehicle speed, ending to clear the braking recovery capability; Determining the current change slope of the braking recovery capability includes: In response to the braking recovery capacity being greater than the current braking recovery torque request value, determining the change slope to be a first slope; In response to the braking recovery capacity being less than or equal to a current braking recovery torque request value, the changing slope is determined to be a second slope.

2. The vehicle energy recovery method according to claim 1, characterized in that: The method further comprises: acquiring motor data, an allowable battery charging power, and a preset coasting regenerative torque of the vehicle, wherein the motor data includes at least motor speed, motor external characteristics, and motor efficiency, and the preset coasting regenerative torque is used to represent the braking regenerative torque of the vehicle during coasting; determining a braking recovery capability corresponding to the vehicle stability controller based on the acquired motor data, the battery allowable charging power, and the preset coasting recovery torque; The braking regeneration capability is sent to the vehicle body stability controller, wherein the braking regeneration capability is used to control the vehicle body stability controller to send the braking regeneration requirement torque, and the braking regeneration requirement torque is less than or equal to the braking regeneration capability.

3. The vehicle energy recovery method according to claim 2, characterized in that: Determining a braking recovery capability corresponding to the vehicle stability controller based on the acquired motor data, the battery allowable charging power, and the preset coasting recovery torque includes: determining a first required torque based on the motor data and the battery allowable charging power; Obtaining a minimum value between the first required torque and the preset coasting recovery torque to determine a second required torque; The difference between the first required torque and the second required torque is obtained to obtain the braking recovery capability.

4. The vehicle energy recovery method according to claim 2, characterized in that: Sending the braking recovery capability to the vehicle stability controller includes: In response to the total required torque being less than a preset threshold and after waiting for a preset time, the braking recovery capability is sent to the vehicle stability controller.

5. The vehicle energy recovery method according to claim 1, characterized in that: In response to a first vehicle speed of the vehicle being less than a first preset vehicle speed and the first vehicle speed being greater than a second preset vehicle speed, starting to clear the braking recovery capability includes: clearing the braking recovery torque; In response to the braking recovery torque being cleared, the second required torque is cleared.

6. A vehicle energy recovery method and device, characterized in that: include: a first determination module for determining a driver demand torque based on the braking command in response to receiving the braking command; a processing module, configured to process the driver's required torque using a five-segment slope filtering algorithm to obtain a target required torque; a first acquisition module, configured to acquire the sum of the braking recovery required torque sent by a vehicle body stability controller in the vehicle and the target required torque to obtain a total required torque; a control module configured to control a motor in the vehicle based on the total required torque; The device is further configured to, after controlling the motor in the vehicle based on the total required torque, obtain a current braking regeneration torque request value of the vehicle stability controller in response to the accelerator pedal of the vehicle being in a priority operating state, wherein the current braking regeneration torque request value is used to represent the braking regeneration torque currently required by the vehicle stability controller; determine a change slope of a braking regeneration capability based on the current braking regeneration torque request value, wherein the change slope includes at least: a first slope and a second slope; clear the braking regeneration capability according to the change slope of the braking regeneration capability; in response to a first vehicle speed of the vehicle being less than a first preset vehicle speed and the first vehicle speed being greater than a second preset vehicle speed, start clearing the braking regeneration capability, and in response to a second vehicle speed of the vehicle being less than or equal to the second preset vehicle speed, end clearing the braking regeneration capability; The device is further configured to determine the change slope to be a first slope in response to the braking recovery capability being greater than the current braking recovery torque request value; and to determine the change slope to be a second slope in response to the braking recovery capability being less than or equal to the current braking recovery torque request value.

7. A computer-readable storage medium, characterized in that The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the vehicle energy recovery method according to any one of claims 1 to 5.

Images